Mechanically interlocked two-dimensional polymers

Abstract

Mechanically interlocked two-dimensional polymers and methods of making and using the same are disclosed.

Description

[0001] MECHANICALLY INTERLOCKED TWO-DIMENSIONAL POLYMERS

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of and priority to U.S. Patent Application No. 63 / 684,251, filed on August 16, 2024, and U.S. Patent Application No. 63 / 733,887, filed on December 13, 2024, which are incorporated by reference herein in their entireties.

[0004] BACKGROUND

[0005] Mechanical bonds, which are comprised of interlocked molecular subunits that are separable only by breaking or distorting their chemical bonds, emerged as functional components of mechanically interlocked molecules with the development of template-directed methods for their synthesis (7,2). These synthetic breakthroughs enabled the field of molecular nanotechnology, in which the controlled relative motions of the molecular subunits are leveraged in molecular switches and motors (3-5), information storage systems (6), and other out-of- equilibrium systems (7,8). Mechanical bonds should also confer unique mechanical or stimuli- responsive characteristics to polymers or bulk materials (9-13). This potential is largely unfulfilled since monomers containing mechanical bonds are challenging to prepare in sufficient amounts and forming mechanical bonds during polymerizations is inefficient. These limitations are most stark for macromolecules in which mechanical bonds hold the extended structure together. For example, the most effective methods to form poly [ / / ] catenanes - polymer chains comprised of n interlocked macrocycles -are presently limited to milligram quantities and modest chain lengths (n ~ 15) (14). As such, predictions of the unique mechanical properties that arise from the mechanically interlocked structure have yet to be validated experimentally, and two-dimensional (2D) polymers linked by mechanical bonds are unknown. Therefore, there remains a need for highly efficient methods to form mechanical bonds, especially to produce extended mechanically interlocked materials (MIMs), will impart unique mechanical, thermal, and stimuli-responsive properties and provide access to entirely new polymer architectures.

[0006] SUMMARY OF THE INVENTION

[0007] The present disclosure provides mechanically interlocked two-dimensional polymers and methods of making the same. The mechanically interlocked two-dimensional polymer may include linkages. In further embodiments, the linkages are siloxane linkages. The crosslinking reagent may be a silane, a phosphene, triphosgene, or a chloroformate reagent. In preferred embodiments, the crosslinking reagent is a silane, and the silane is a dialkyldichloro silane or alkyltrichloro silane. Exemplary dialkyldichloro silanes include but are not limited to dichlorodimethylsilane (SiNfeCh), dichlorodiphenylsilane, dichloromethylcyclohexylsilane, dichloromethylvinylsilane, or trichloromethyl silane.

[0008] The disclosure further provides a fiber including the polymer composite described herein, wherein the fiber has average fiber diameter less than 5 am, less than 4 p , less than 3 pm, less than 2 pm, or less than 1 pm.

[0009] The present disclosure also provides a method for preparing a mechanically interlocked two-dimensional polymer. The method includes contacting a crystalline monomer with a crosslinking reagent, wherein the crystalline monomer includes two sets of parallel linear structures and the two sets of parallel linear structures tread through each other.

[0010] The present disclosure also provides a method for preparing a mechanically interlocked two-dimensional polymer as described herein. The method includes contacting a crystalline monomer with a crosslinking reagent.

[0011] The present disclosure also provides a dispersion including the mechanically interlocked two-dimensional polymer described herein and a solvent. The solvent may include an organic solvent. Exemplary organic solvents include but are not limited to acetone, isopropyl alcohol, tetrahydrofuran, ethyl acetate, or any combination thereof.

[0012] The disclosure further provides a method of preparing a dispersion. The method includes dispersing the mechanically interlocked two-dimensional polymer as described herein or prepared by the methods described herein in a solvent. In some embodiments, the solvent is an organic solvent.

[0013] A polymer composite including the mechanically interlocked two-dimensional polymer and a second polymer is also provided herein. In some embodiments, the second polymer is poly(ether imide).

[0014] A method of preparing a polymer composite is also described herein. The method includes mixing the mechanically interlocked two-dimensional polymer described herein or prepared according the methods described herein and a second polymer. The present disclosure also provides a method of preparing a fiber. The method includes electrospinning the polymer composite described herein or prepared according to the methods described herein.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying figures, which are schematic and are not intended to be drawn to scale. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the invention shown where illustration is not necessary to allow those of ordinary skill in the art to understand the invention.

[0017] Figure 1. A) Schematic of the solid-state polymerization of TPE-PhOH and SiNteCb to form the 2D MIM. SiMe2Ch is introduced to the TPE-PhOH crystals either from the vapor phase or as a solution in hexanes, which does not dissolve the crystals. B) Single crystal x-ray diffraction structural models of the TPE-PhOH monomer prior to polymerization. Left: Side-on view of the alternating 2D hydrogen-bonded layer of TPE-PhOH molecules and ordered ethyl acetate solvent molecules. Middle: top-down view of a single 2D molecular layer of the TPE-PhOH crystal with solvent molecules excluded; perpendicular linear arrangements of TPE-PhOH molecules are supported by hydrogen bonds. Right: The alkene of TPE-PhOH molecule threads through a cavity created by the hydrogen bonded arrangements of two adjacent TPE-PhOH molecules and vice- versa. Likewise, the alkene of TPE-PhOH molecule threads through the analogous cavity formed by adjacent TPE-PhOH molecules.

[0018] Figure 1. A) Schematic of 2D MIM polymerization and processing. First, TPE-PhOH crystallizes into large single crystals. Then those crystals react with SiMe2Chto form the 2D MIM. After polymerization, the 2D MIM is dispersible in common organic solvents including acetone, isopropyl alcohol, tetrahydrofuran, and ethyl acetate. As a dispersion, the 2D MIM was precipitated into a non-solvent for purification and collected by filtration for characterization. B) XPS and C)13C CP-MAS NMR spectra of TPE-PhOH (black) and 2D MIM (grey) confirming successful conversion of TPE-PhOH into the 2D MIM. D) AFM image of a single 2D MIM sheet isolated by drop casting 2D MIMs from tetrahydrofuran onto a silicon wafer. The sheet retains the square morphology of the starting TPE-PhOH crystal and a uniform few-nm height that we assign to a single molecular layer. E) SEM image of 2D MIM sheets isolated by drop casting 2D MIMs from isopropanol onto a silicon wafer.

[0019] Figure 2. S / TEM micrographs of 2D MIM. A) tcBF image depicting the well-ordered atomic structure of 2D MIM, suggesting a highly crystalline structure and local distortion (arrow) caused by sheet flexibility. B-C) Comparison of tcBF image and the schematic atomic structure of 2D MIM showing the agreement between the zig-zag pore structure if carbon chain in the modeled and imaged 2D MIM. D) SAED pattern of 2D MIM indicating its single crystalline nature and d- spacing. E) Virtual HAADF image of 2D MIM from 4D STEM data, suggesting thickness variance of 2D MIM over pm-level field of view caused by sheet flexibility (brighter areas are thicker). F- G) Real space and corresponding diffraction space components (by different colors) of the 4D STEM dataset indicating that the 2D MIMs are wrinkling along the z axis, causing large tilt angle differences.

[0020] Figure 3. (A) SEM micrographs showcase average fiber diameters of <5 gm and high alignment along the drum rotation direction (vertical). (B) Tensile plots showcasing the mechanical enhancement provided by the 2D MIM. Incorporation of highly exfoliated 2D MIM filler exhibited higher ultimate stress and tensile modulus (E’) up to 2.5 wt% MIMs, whereafter mechanical performance was diminished. (C) Statistical analysis of tensile properties of 2D MIM / Ultem™ poly(ether imide) composite fibers across a compositional range. Samples comprised of 2.5 wt% MIM exhibited the highest tensile modulus and UTS, but all compositions displayed reduced strain at break compared to nascent Ultem™ All pair-wise comparisons not shown were significant.

[0021] Figure 5. Representative 'H NMR spectra of catalyst selection experiments.

[0022] Figure 6. UV / Vis spectra of the 2D MIM in various solvents shows normal aggregation induced emission behavior known for tetraphenylethylene (TPE) chromophores. The Xmax of the 2D MIM red-shifts with increased solvent viscosity, corresponding to slower rotation about the phenyl rings. Each spectrum is normalized at its Xmax. Solvent viscosity at 298 K (cP) are listed in the legend.

[0023] Figure 7. Fluorescence spectra of the 2D MIM in various solvents shows increased emission intensity with increased solvent viscosity. Inset: Normalized fluorescence spectra indicating that the peak does not shift. Figure 8. A) TEM image of the 2D MIM along c axis, shows a lot of bend contours (arrow) indicating local bending in a single nanosheet, and some Moire patterns (arrow) from overlapping domain, and B) its corresponding SAED pattern suggesting its single crystal nature, the diffraction index and their corresponding d spacing. The intensity of

[0100] and

[0010] diffraction spots are much dimmer than

[0200] and

[0020] , suggesting that there are small distortions between nearby unit cell in ab plane, which make them appear weakly after destructive interference (if 2D MIM is perfect crystal,

[0100] and

[0010] diffraction spots should be forbidden). Based on the difference in the d spacings of

[0100] and

[0010] , the unit cell of 2D MIM is orthorhombic instead of cubic.

[0024] Figure 9. A) HAADF-STEM image of the 2D MIM (brightness is related to thickness) and B) relative thickness map from an EELS measurement using a log-ratio method.

[0025] Figure 10. SAED pattern and the average diffraction pattern of the whole SEND (or 4DSTEM) data are in principle identical with different diffraction disk sizes, suggesting that in the field of view of 4DSTEM, the 2D MIM appears to be a single crystal instead of poly crystal. Virtual HAADF image of the 4DSTEM data indicates the real space information in field of view.

[0026] Figure 11. A-D) 4D-STEM data with corresponding diffraction pattern (top) and real space components (bottom). E) overlap of the four regions. These data show that even though the average diffraction pattern is single crystalline, the 2D MIMs bend locally in the ab plane resulting in large tilt at different angles.

[0027] Figure 12. iDPC-STEM image (left) of 2D MIM and its corresponding FFT patterns (right). FFT patterns show: top right) whole image, middle right) outlined section 1, bottom right) outlined section 2. The different FFT patterns of the iDPC image from regions 1 and 2 indicate that the 2D MIM lattice is around 5.30 A and that there are a lot of local tilt even in this 100 nm x 100 nm field of view.

[0028] Figure 13. iDPC-STEM image of 2D MIM versus tcBF images of the same field of view (but different regions), the tcBF image has better contrast and resolution which shows more details of the structure of the 2D MIMs.

[0029] Figure 14. SCI structure model viewed along the C axis.

[0030] Figure 15. Nanoindentation measurements on 2D MIM with normal force of 50 pN indicate that at low loading forces the 2D MIM acts elastically with the material recovering fully after each of the five loading cycles. Figure 16. Nanoindentation measurements on 2D MIM with higher normal forces indicate that with an addition of 300 pN normal force and above the material exhibits a J-shaped loading curve typical of interlocked materials.

[0031] Figure 17. SEM micrographs before and after boiling in water for 1 hour.

[0032] DETAILED DESCRIPTION OF THE INVENTION

[0033] The present disclosure provides mechanically interlocked two-dimensional polymers (2D MIMs) and methods of making the same. Two-dimensional polymers are macromolecules that extend in two spatial dimensions, forming sheet-like structures with repeating units arranged in a planar lattice. When mechanical interlocking is incorporated into these two-dimensional polymer frameworks, the result is a material that combines the structural order of two-dimensional polymers with the properties of mechanically interlocked systems.

[0034] Topochemical polymerizations efficiently link monomers that crystallize with polymerizable groups in proximity. We hypothesized that this crystal engineering concept could be elaborated to form mechanical bonds with unprecedented efficiency. These reactions rely on the principle that molecules in the solid state undergo minimal molecular movement, which can give rise to highly efficient and selective reactions when reactive groups fall within a narrow range of suitable distances and relative orientations (75, 76). The first topochemical polymerizations relied on photochemical [2+2] cycloaddition reactions (77), which were later expanded to other photochemical and thermal reactions (75) and to form single-crystalline 2D polymers (19-21)' . Solid-state polymerizations between a crystallized monomer and an exogenous, mobile comonomer would dramatically expand the versatility of these polymerizations, including potentially templating macrocyclizations or forming mechanical bonds. Herein this concept in the form of a solid-state two-dimensional polymerization in which a new macrocycle and mechanical bond is formed at every repeat unit is introduced. The monomer crystal has a layered, two- dimensional structure supported by hydrogen-bonds between proximal hydroxyl groups, which react selectively to form linkages (e.g., siloxane linkages) with a crosslinking reagent (e.g., dialkyldi chlorosilane) introduced either from the vapor phase or a nonsolvent for the crystal. These copolymerizations are operationally simple, use readily available monomers, and have been conducted on a multi gram scale. The resulting 2D MIM is a previously unreported macromolecular architecture with the highest density of mechanical bonds ever achieved (106mechanical bonds / pm2of each 2D polymer layer). Although formed as a multilayer structure reminiscent of other layered 2D polymers, the 2D MIM is readily exfoliated and dispersed in common organic solvents, which facilitated its purification and characterization. Atomic-resolution imaging of its periodic, individual sheets using electron microscopy provided strong evidence for its highly crystalline yet flexible structure. Its solution processibility enabled co-electrospinning of 2D MIMs with Ultem™ at significant amounts (1-10 wt%) yielding composite poly(ether imide) fibers that exhibited a 45% increase in tensile modulus (E ) and 22% increase in tensile strength at 2.5 wt% 2D MIM content. These findings introduce the feasibility of solid-state polymerizations between a crystalline monomer and an exogenous comonomer, the power of this strategy to produce otherwise inaccessible interlocked polymer architectures, and 2D MIMs as a distinctive new polymer class for fundamental and applied studies.

[0035] The present disclosure provides mechanically interlocked two-dimensional polymers and methods of making the same. The mechanically interlocked two-dimensional polymer may include linkages. In further embodiments, the linkages are siloxane linkages.

[0036] The mechanically interlocked two-dimensional polymer may be prepared from a crystalline monomer. In some embodiments, the mechanically interlocked two-dimensional polymer is exfoliated.

[0037] The mechanically interlocked two-dimensional polymer may be prepared from a precursor having a functional group capable of reacting with a crosslinking regent to prepare the polymer. Suitablly, the precursor may have one, two, three, four, or more than for functional groups. The functional groups may also facilitate the preparation of a crystalline monomer via non-covalent interactions, such as hydrogen bonding interactions. The Examples demonstrate the suitability of hydroxyl groups to prepare the mechanically interlocked two-dimensional polymer but other functional groups may be used. In some embodiments, the mechanically interlocked two- dimensional polymer is prepared from TPE-PhOH.

[0038] The mechanically interlocked two-dimensional polymer may be prepared with a crosslinking reagent capable of reacting with the functional groups of the precursor. In some embodiments, the mechanically interlocked two-dimensional polymer is prepared from a silane. In preferred embodiments, the silane is a dialkyldichloro silane or alkyltrichloro silane. Exemplary dialkyldichloro silanes include but are not limited to dichlorodimethylsilane (SiMe2Ch), dichlorodiphenylsilane, dichloromethylcyclohexylsilane, dichloromethylvinylsilane, or trichloromethylsilane. In other embodiments, the crosslinking reagent is phosgene, triphosgene, or a chloroformate reagent.

[0039] The disclosure further provides a fiber including the polymer composite described herein, wherein the fiber has average fiber diameter less than 5 p , less than 4 pm, less than 3 pm, less than 2 pm, or less than 1 pm.

[0040] The present disclosure also provides a method for preparing a mechanically interlocked two-dimensional polymer. The method includes contacting a crystalline monomer with a crosslinking reagent, wherein the crystalline monomer includes two sets of parallel linear structures and the two sets of parallel linear structures tread through each other. The crosslinking reagent suitable will not destroy the order of the two sets of parallel linear structures that are threaded through each other. The crosslinking reagent may be a silane, a phosphene, triphosgene, or a chloroformate reagent. In preferred embodiments, the crosslinking reagent is a silane, and the silane is a dialkyldichloro silane or alkyltrichloro silane. Exemplary dialkyldichloro silanes include but are not limited to dichlorodimethylsilane (SiNfeCh), dichlorodiphenylsilane, dichloromethylcyclohexylsilane, dichloromethylvinylsilane, or trichloromethylsilane.

[0041] In some embodiments, the mechanically interlocked two-dimensional polymer prepared by the methods described herein yield a crystal. The crystals may be rhombic structures with one side of about 1 micron in length. In some embodiments, the crystals 10 microns, 50 microns, 100 microns, and up to 750 microns, as well as sizes in between these ranges.

[0042] In some embodiments, the crystalline monomer is contacted with reagent vapor. The crystalline monomer may be contacted with the reagent in a non-solvent of the crystalline monomer. The non-solvent of the crystalline monomer may include alkanes. In some preferred embodiments, the alkanes include one or more hexane isomers. The crystalline monomer described herein may include TPE-PhOH.

[0043] The method may further include exfoliating the mechanically interlocked two-dimensional polymer. The method may prepare the mechanically interlocked two-dimensional polymer as described herein.

[0044] The present disclosure also provides a method for preparing a mechanically interlocked two-dimensional polymer as described herein. The method includes contacting a crystalline monomer with a crosslinking reagent. The crosslinking reagent may be a silane. In preferred embodiments, the silane is a di alkyl di chloro silane or alkyltrichloro silane. Exemplary di alkyl di chloro silanes include but are not limited to di chlorodimethyl silane (SiMezCh), dichlorodiphenylsilane, dichloromethylcyclohexylsilane, dichloromethylvinylsilane, or trichloromethylsilane. In other embodiments, the crosslinking reagent is phosgene, triphosgene, or a chloroformate reagent.

[0045] In some embodiments, the mechanically interlocked two-dimensional polymer prepared by the methods described herein yield a crystal. The crystals may be rhombic structures with one side of about 1 micron in length. In some embodiments, the crystals 10 microns, 50 microns, 100 microns, and up to 750 microns, as well as sizes in between these ranges.

[0046] The present disclosure also provides a dispersion including the mechanically interlocked two-dimensional polymer described herein and a solvent. The solvent may include an organic solvent. Exemplary organic solvents include but are not limited to acetone, isopropyl alcohol, tetrahydrofuran, ethyl acetate, or any combination thereof.

[0047] The disclosure further provides a method of preparing a dispersion. The method includes dispersing the mechanically interlocked two-dimensional polymer as described herein or prepared by the methods described herein in a solvent. In some embodiments, the solvent is an organic solvent.

[0048] A polymer composite including the mechanically interlocked two-dimensional polymer and a second polymer is also provided herein. In some embodiments, the second polymer is poly(ether imide).

[0049] The composite may include between 0.1 and 10.0 wt%, between 0.1 and 5.0 wt%, between 0.5 and 5.0 wt%, between 1.0 and 5.0 wt%, or between 1.0 and 4.0 wt%, or between 2.0 and 3.0 wt% of the mechanically interlocked two-dimensional polymer.

[0050] A method of preparing a polymer composite is also described herein. The method includes mixing the mechanically interlocked two-dimensional polymer described herein or prepared according the methods described herein and a second polymer. In some embodiments, the second polymer is a poly(ether imide).

[0051] The present disclosure also provides a method of preparing a fiber. The method includes electrospinning the polymer composite described herein or prepared according to the methods described herein. Unless otherwise specified or indicated by context, the terms “a”, “an”, and “the” mean “one or more.” For example, “a molecule” should be interpreted to mean “one or more molecules.”

[0052] As used herein, “about”, “approximately,” “substantially,” and “significantly” will be understood by persons of ordinary skill in the art and will vary to some extent on the context in which they are used. If there are uses of the term which are not clear to persons of ordinary skill in the art given the context in which it is used, “about” and “approximately” will mean plus or minus <10% of the particular term and “substantially” and “significantly” will mean plus or minus >10% of the particular term.

[0053] As used herein, the terms “include” and “including” have the same meaning as the terms “comprise” and “comprising.” The terms “comprise” and “comprising” should be interpreted as being “open” transitional terms that permit the inclusion of additional components further to those components recited in the claims. The terms “consist” and “consisting of’ should be interpreted as being “closed” transitional terms that do not permit the inclusion additional components other than the components recited in the claims. The term “consisting essentially of’ should be interpreted to be partially closed and allowing the inclusion only of additional components that do not fundamentally alter the nature of the claimed subject matter.

[0054] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0055] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0056] Preferred aspects of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred aspects may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect a person having ordinary skill in the art to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

[0057] EXAMPLES

[0058] TPE-PhOH has been previously crystallized into a layered structure that align the TPE- PhOH molecules with two sets of parallel, hydrogen-bonded linear structures that are oriented at 90° with respect to each other (22). The central carbon-carbon double bond of each TPE-PhOH molecule threads through the hydrogen-bond supported macrocycle of a perpendicular thread. The previously reported crystals featured disordered solvent molecules between each molecular layer. We obtained distinct but analogous crystals of TPE-PhOH from ethyl acetate. These structures feature linear arrangements of TPE-PhOH in which an alcohol group on one monomer donates a hydrogen-bond to an oxygen on the adjacent monomer, which in turn hydrogen-bonds to the carbonyl oxygen of ethyl acetate (Figure IB, right). Overall, these linear, hydrogen-bonded assemblies form 2D networks, with ordered ethyl acetate molecules separating each 2D sheet (Figure IB, left). We later developed a crystallization procedure amenable to larger scale formation of the TPE-PhOH crystals by partial evaporation of the ethyl acetate solution to supersaturation using a rotary evaporator. This procedure proved more reproducible when 5% v / v glacial acetic acid was added. Both methods produced the same crystal structure, which was amenable to the 2D polymerization methods described below. We also found that previous syntheses of TPE-PhOH were not amenable for larger-scale synthesis required to explore 2D polymer properties. Specifically, TPE-PhOH was difficult to separate from incomplete coupling products in its key Suzuki-Miyaura cross-coupling reaction, and it co-crystallized with triphenylphosphine oxide derived from the Pd(PPhs)4 catalyst (SC2, Figure 14). Therefore, we developed an improved synthesis using Pd(OAc)2 and an exogenous S-Phos ligand, which achieves a highly efficient Suzuki-Miyaura cross-coupling reaction and provides pure TPE-PhOH with no chromatographic purification steps. Using this procedure, we scaled the synthesis of TPE- PhOH to 50 g batches in 85% isolated yield.

[0059] The polymerization between TPE-PhOH single crystals and SiMe2Ch forms 2D MIMs (Figure 1A). The arrangement of TPE-PhOH molecules in the 2D hydrogen-bonded crystals position two hydroxyl groups separated by 2.824 A, enabling their specific reaction with SiMe2Cb. The dichlorosilane monomer was first introduced by passive diffusion into the TPE-PhOH crystals from the vapor phase over one week. Later, the polymerization was performed in hexanes, a non-solvent for TPE-PhOH crystals, with reduced reaction times of 12-24 hours and increased scale to more than 10 grams of the 2D MIM isolated per batch. Elemental analysis confirmed the polymerization of TPE-PhOH monomer crystals into the 2D MIM. Inductively coupled plasma optical emission spectroscopy (ICP-OES) of the 2D MIMs polymerized in hexanes indicated Si incorporation of 7.54 ± 0.5% compared to the expected value of 6.91%, along with Cl content (by titration) that was near baseline levels (0.16 ± 0.4%). The low residual Cl levels suggest efficient reactions of the SiMe2Ch and that HC1 can exit the solid during polymerization. Additionally, the carbon and hydrogen content of 83.45 ± 0.3% and 5.36 ± 0.3%, respectively, are relatively consistent with their expected values of 80.28% and 5.42%. These data indicate that the polymerization reaction occurs successfully. Further, x-ray photoelectron spectroscopy (XPS) was employed to characterize the composition and bonding environment of the monomer and 2D MIMs. The carbon environments of the monomer and polymer appear largely unchanged with the major carbon peak appearing at 284.0 eV in both spectra consistent with the majority of carbons being incorporated in aromatic rings (23) (Figure 2B). However, the XPS oxygen peak shifts in binding energy from 531.6 eV, consistent with that of a phenol group, to 532.1 eV, which is consistent with the formation of O-Si bonds (24) (Figure 2B). Further, the XPS of the 2D MIM also features a prominent Si peak not present in the monomer crystal and a chlorine peak that is barely above the baseline, both of which are consistent with the bulk elemental analysis results (Figure 2B). Additionally,13C cross-polarization magic angle spinning nuclear magnetic resonance (CP-MAS NMR) spectroscopy confirms that the silane comonomers react with the alcohols of TPE-PhOH with only small shifts to its aromatic resonances (Figure 2C). The CP- MAS NMR spectrum of the 2D MIM shows two new resonances at 154.6 ppm and 116.1 ppm, which correspond to the carbons attached to the oxygens and the carbons ortho to the silyl ether groups, respectively. The polymerization also incorporates two methyl groups per silicon atom, which resonate at 17.2 ppm. Additionally,29Si NMR spectroscopy indicates the incorporation of a single silicon peak centered at -21.308 ppm. These elemental analyses, XPS, and13C CP-MAS NMR spectroscopy data indicated that the alcohols of the TPE-PhOH reacted with SiMe2C12to form siloxane bonds and polymerize the monomer crystals into the 2D MIM. In contrast to layered 2D polymers known as covalent organic frameworks (25), 2D MIMs have weak interlayer interactions that enable their exfoliation and dispersion in common organic solvents. This characteristic endows 2D MIMs with facile solution processability well beyond that of other 2D polymers. When dissolved in various solvents, the 2D MIMs exhibit the characteristic solvatochromism and normal aggregation induced emission behavior of its tetraphenylethene subunits (26). The wavelength of maximum absorbance (Amax) red shifts across solutions of increasing viscosity (Figure 6) and the fluorescence intensity increases with increased solvent viscosity (Figure 7). These observations are consistent with the expected polymer structure and indicate that its phenyl rings freely rotate and respond to their solvent environment. After exfoliation, the polymer sheets maintain their square morphology when deposited on silicon substrates. The exfoliated 2D MIMs maintain an average size of 12.5 pm measured by scanning electron microscopy (SEM, Figure 2E) and appear to be individual sheets with smooth surfaces and no observed step edges as measured by atomic force microscopy (AFM, Figure 2D) and further confirmed by electron energy loss spectroscopy (EELS, Figure 9). After exfoliation, the 2D MIMs are amenable to conventional polymer precipitation techniques by adding the exfoliated 2D MIM solution into an anti-solvent. The sheets then precipitate from solution and are collected via filtration or centrifugation (Figure 2A). Dispersions of the 2D MIM in 80:20 acetone-d6:H2O showed no evidence of hydrolysis by NMR spectroscopy after 24 hours at room temperature and then another 22 hours at 55 °C. The processability of 2D MIMs is highly advantageous for forming composites (see below) or other potential applications in which 2D polymers are promising yet difficult to incorporate.

[0060] Exfoliation of the 2D MIM into thin nanosheets enabled investigation of the angstromlevel structural detail by various electron microscopy techniques. Integrated differential phase contrast scanning transmission electron microscopy (iDPC-STEM) imaging yielded atomic- resolution images. The iDPC-STEM image and the fast Fourier transform (FFT) of that image revealed that the square pores of 2D MIMs range in size from 5.24 to 5.30 A, a 2 - 3% decrease respectively compared to the monomer crystal, and that the polymer sheet has a fair amount of local bending within a 100 nm x 100 nm region, as evidenced by variations in the FFT patterns from different areas (Figure 12). Tilt-corrected bright field (tcBF) imaging (27), which is more dose-efficient than iDPC-STEM and thus provided higher resolution (Figure 13), clearly depicted pore size around 5.30 A and the long-range structure of the 2D MIM consistent with its modeled structure (Figure 3A-3C). Additionally, within a 28 nm x 28 nm field of view (Figure 3A), two distinct regions occur in the lower left and middle, characterized by areas that are not perfectly on- zone (Figure 3A). This observation, supported by both selected area electron diffraction (SAED) (Figure 3D) and scanning electron nanobeam diffraction (SEND or four-dimensional scanning transmission electron microscopy 4D-STEM) data, shows the atomic-resolution structure bending and tilting, further exemplifying the inherent flexibility of the 2D MIMs.

[0061] The 2D MIMs exhibit abundant bend contours and moire patterns in bright-field transmission electron microscopy images (Figure 8). 4D-STEM provides insight into these moire patterns by simultaneously probing real-space and reciprocal-space information about the local bending and crystal structure. The average diffraction pattern from the 4D-STEM data exhibited diffraction spots in all directions, similar to the inner diffraction spots seen in SAED (Figure 10). Segmentation of the diffraction patterns corresponding to each real-space region identified clusters of real-space areas each with characteristic diffraction patterns (Figure 11). The thicker, brighter regions in the virtual high-angle annular dark-field (HAADF) images (Figure 3E-3G) represent wrinkles in the 2D polymer which cause significant bending angles. Therefore, the bend contour observed in SAED stem from the local tilts and rotations inherent to the soft, undulating structure of the 2D MIM. Collectively, these electron microscopy techniques provide a comprehensive understanding of the highly crystalline yet ultra-flexible nature of the 2D MIM.

[0062] Quantitative nanomechanical mapping (QNM) and nanoindentation analyses provided responses consistent with the structure of the 2D MIM. QNM analysis on the 2D MIM provided a modulus of 5.36 GPa, which is three orders of magnitude higher than the modulus reported for the TPE-PhOH monomer crystals (4.75 MPa) (22). When wetted with a mixture of IP A and water, the 2D MIMs form a paste that was spreadable onto glass slides. Once dried, this form was amenable to nanoindentation measurements. Small normal loading forces (50 pN) the 2D MIM induced elastic deformation (Figure 15), which were consistent for six consecutive loading / unloading curves. Incrementally larger loading forces induced distinct deformation patterns, as indicated by the curve shapes (Figure 16). Once 100 pN normal force was applied, the material underwent plastic deformation, which remained after the unloading process. Normal forces of 300 pN or higher produced loading curves with distinct J shapes, which correspond to stiffening of the material towards the end of the loading process. This stiffening is consistent with a mechanically interlocked structure, corresponding to stretching the mechanical bonds to their limits and the onset of material deformation.

[0063] To further probe the properties of 2D MIMs, they were incorporated into polymer-polymer composite fibers. Electrospinning 2D MIMs / Ultem™ poly(ether imide) solutions formed fibers with consistent diameter and surface morphology (Figure 4A). These fiber mats underwent uniaxial tensile testing to probe their mechanical properties. Given that these fiber mats have considerable void space, the mechanical results were corrected for the material density as measured by pycnometry. After correction, the 2D MIM / Ultem™ poly(ether imide) composites with 1 and 2.5 wt% 2D MIM incorporation show enhanced properties with significantly higher tensile modulus (E’, 30 and 45 %, Figure 3C, left) and ultimate stress (2.4 and 22 %, Figure 4C, middle) than pure Ultem™ poly(ether imide) fibers with a decrease in the strain at break (64 and 53%, Figure 4c, right). However, the incorporation of 5 wt% or higher 2D MIM leads to diminished performance compared to the lower content composites. These higher content composites, while diminished compared to the low content composites, exhibit properties in line with the Ultem™ poly(ether imide) fibers. We hypothesize that the decrease in properties for composites containing more than 2.5 wt% 2D MIM is caused by aggregation of the 2D MIMs which inhibited efficient stress transfer from the matrix to the 2D MIM filler. The mechanical enhancement of the composites remained after they were vigorously boiled in water for 1 hour and dried (Figure 17). These mechanical results exemplify the unique properties of the 2D MIMs in their ability to increase the stiffness and strength of materials.

[0064] Materials

[0065] Tetrabutylammonium bromide (99+%, Fischer Scientific), 1,4-dioxane (certified ACS, Fischer Scientific), dicyclohexyl(2’,6’-dimethoxy[l,l’-biphenyl]-2-yl)phosphine (SPhos, Ambeed), palladium (II) acetate (Ambeed), di chlorodimethylsilane (MilliporeSigma), 4’ -hydroxy - [l,l’-biphenyl]-4-yl)boronic acid (Fischer Scientific), l,l,2,2-tetrakis(4-bromophenyl)ethene (Ambeed), hydrochloric acid (Fisher Scientific), ethyl acetate (reagent grade >99.5%, MilliporeSigma), 1,4-dioxane (certified ACS, Fisher Chemical), magnesiumsulfate (Fisher Scientific), Celite (Fisher Scientific), acetone (certified ACS, Fisher Chemical), acetonitrile (certified ACS, Fisher Chemical), XPhos Pd G3 (MilliporeSigma), XPhos (MilliporeSigma), hexanes (certified ACS, Fisher Scientific), tetrahydrofuran (ACS Reagent, inhibited with butylatedhydroxytoluene, Fisher Scientific), and isopropanol (MilliporeSigma) were used as received.

[0066] Silicon wafers for microscopy (SiC>2 / Si 4” wafers) were purchased from University Wafer. Uncoated wafers were: cut down to 1 cm squares, sonicated in IP A, and dried under ambient conditions prior to use.

[0067] Polyetherimide, Ultem™ (Sigma-Aldrich, MFI 9) and N-methylpyrrolidone (NMP) (anhydrous, 99.5%) were used as received.

[0068] Instrumentation

[0069] Nuclear Magnetic Resonance (NMR) Spectroscopy. NMR spectroscopy was conducted at the Integrated Molecular Structure Education and Research Center (IMSERC) at Northwestern University. Liquid spectra were taken on a 400 MHz Bruker Avance III HD system equipped with a BBO prodigy probe with z-gradient equipped with a samplexpress autosampler.

[0070] 29Si Solid State NMR. The29Si{ 1 } cross-polarization with Carr-Purcell-Meiboom-Gill (CPMG) solid state nuclear magnetic resonance (SSNMR) spectra were recorded on a 400 MHz Bruker Avance III HD NMR Spectrometer with a 4 mm HX probe. The frequency of1H and29Si nuclei are 399.7 MHz and 79.4 MHz.29Si{ 1 } CPMAS spectra were acquired with an initial 'H zr / 2 pulse width of 2.35 ps,1H-29Si cross-polarization Hartman-Hahn contact time of 5 ms, 58000 transients and a recycle delay of 1.3 s. For CPMG acquisition, the echo delay was set to 7.2 ms. The sample was spun at 10 kHz. Solid state of 29Si spectra were referenced to an external solid tetrakistrimethylsilane at 5 -9.8 ppm.

[0071] Cross-Polarization Magic Angle Spin Nuclear Magnetic Resonance (CP-MAS NMR) Spectroscopy. CP-MAS NMR spectroscopy was conducted at IMSERC at Northwestern University. Solid state spectra were collected using CP-MAS program on a 400 MHz Bruker Avance III HD system equipped with a 4 mm HX probe (funding from the NSF CHE-9871268 and International Institute of Nanotechnology).

[0072] Atomic Force Microscopy (AFM). AFM was conducted at the Northwestern University’ s Atomic and Nanoscale Characterization Experimental Center (NUANCE). Samples were drop cast from solution onto SiOz / Si wafers. The wafers were allowed to dry overnight under ambient conditions. AFM was conducted using the Bruker Icon AFM under normal tapping mode in air.

[0073] Scanning Electron Microscopy (SEM). Samples were drop cast from solution onto SiOz / Si wafers. The wafers were allowed to dry overnight under ambient conditions. The wafers were coated with 1 nm osmium using a SPF Osmium Plasma Coater at NUANCE facilities. Images were taken at NUANCE in the Electron Probe Instrumentation Center (EPIC) on either a Hitachi S-4800 or a Hitachi SU8030 microscopes with an accelerating voltage of 15 kV.

[0074] Energy-Dispersive X-Ray (EDX) Spectroscopy. EDX was performed at NUANCE in the electron probe instrumentation center (EPIC) on a Hitachi SU8030 equipped with an oxford Aztec X-max 80 SDD-EDS detector.

[0075] Thermogravimetric Analysis (TGA). TGA was performed using a Netzsch Simultaneous Thermal Analysis (STA) system.

[0076] Powder X-Ray Diffraction (PXRD). Samples were mounted on disk sample holders using acetate foil. Samples were measured using a STOE Stadi P with pure CuKal radiation in transmission geometry at IMSERC. Powder patterns were processed using GSAS II.

[0077] Single Crystals X-Ray Diffraction (SCXRD). SCXRD data was taken on a Rigaku DW- Synergy with a rotating CuKa and MoKa anode and a HyPix detector. Crystals were removed from solution and mounted on the loop using paratone oil.

[0078] X-Ray Photoelectron Spectroscopy (XPS). XPS was performed on dry powders using a NEXSA G2 instrument. Samples were dried under vacuum for 2 hours then adhered to sample holders with copper tape for data collection. The instrument uses a monochromated micro-focused low-power Al Ka X-ray source with a 180-degree double-focusing, hemispherical analyzer and 128-channel detector. Flood gun was enabled to reduce charging and spectra were charge compensated to aromatic carbon signal at 284 eV.

[0079] Ultraviolet / Visible (UV / VIS) Spectroscopy. UV / Vis spectra were taken using a Cary 5000 UV-Vis-NIR spectrophotometer. The measurements were conducted using quartz cuvettes and a dual beam measurement. Each measurement was done in triplicate and a representative spectra shown.

[0080] Elemental Analysis. C / H / N / Si / Cl analyses were conducted by Robertson Microlit. C / H / N data was measured via combustion with an error of 0.3%. Cl was measured using titration with an error of 0.4%. and Silicon was measured using inductively coupled plasma optical emission spectroscopy (ICP-OES) with an error of 0.5%.

[0081] Fourier-Transform Infrared (FT-IR) Spectroscopy. FT-IR spectroscopy was conducted using a Nicollet iSlO FT-IR spectrometer equipped with a diamond ATR using purified 2D MIM powders. Gas Sorption Isotherms. N2 isotherms of a 62.5 mg sample were measured at 77 K on Micromeritics Tristar II 3020 (Micromeritics, Norcross, GA). Briefly, the materia was degassed overnight under vacuum followed by incremental dosing of nitrogen up to 760 mmHg in a liquid nitrogen (77 K) bath. The Brunauer-Emmett-Teller (BET) surface area was calculated from the linear region of the isotherm using Micromeritics software.

[0082] PeakForce Quantitative NanoMechanical Analysis. PeakForce QNM was conducted at NUANCE. Samples were drop cast from a tetrahydrofuran solution onto graphene coated SiCh / Si wafers. The wafers were allowed to dry overnight under ambient conditions. PeakForce QNM was conducted using the Bruker Icon AFM under peak force quantitative NanoMechanical in air mode.

[0083] Nanoindentation Measurements. Nanoindentation measurements were conducted at NUANCE using a Hysitron TriboIndenter equipped with a 100 nm Berkovich probe.

[0084] For low loading experiments, the sample was subjected to incremental loading, holding, and unloading segments. Loading to 50 pN occurred over 1 second, the material was held at 50 pN for 2 seconds, followed by an unloading to 0 pN over 1 second. This 4 second cycle was then repeated.

[0085] For incrementally higher loading experiments, the sample was subjected to incremental loading, holding, and unloading. The normal force was applied over a period of 2 seconds, followed by a 2 second hold at that force, and a 2 second unloading segment back to 0 pN normal force. The material was then subjected to repeated cycles where the normal force was incrementally increased but the loading, holding, and unloading times remained constant.

[0086] Fluorescence. Fluorescence measurements were taken on a photon-counting fluorescence spectrometer. The ISS PCI spectrofluorimeter is part of the Keck Biophysics Facility at Northwestern university.

[0087] Scanning Transmission Electron Microscopy (STEM). Transmission Electron Microscopy (TEM) and STEM experiments were performed using Thermo-Fisher FEI Spectra 300 TEM with ultra-high-brightness cold field emission gun (C-FEG) and spherical aberration correction (aka. “Kraken” at Cornell University). All EM data were taken at 300 kV. The TEM image and its corresponding SAED are taken with 2 e- / A2, and the SAED pattern is calibrated by the diffractogram of the image. The integral Differentiate Phase Contrast (iDPC) STEM image was collected with C2 aperture = 50 um, and convergence angle = 21.4 mrad with 10 mrad inner and 21.4 mrad out collection angles with 60 e- / A2. All EM experiments are conducted at room temperature.

[0088] Electron Energy Loss Spectroscopy (EELS). The EELS experiment was performed on ‘Kraken’ using Gatan Spectrometer with 45mrad collection angle, 0.75 eV energy resolution and 77 pA probe current. For elemental mapping, L3 edge of Si, K edge of C, K edge of O was integrated. For thickness measurements, log-ratio method was applied. All EM experiments are conducted at room temperature.

[0089] Scanning Electron Nanobeam Diffraction (SEND) or four-dimensional scanning TEM (4D-STEM). The 4DSTEM experiment was performed using Thermo-Fisher Titan Themis Cryo S / TEM with a Field Emission Gun (X-FEG), a monochromator and probe spherical aberration correction. The 4D-STEM dataset was collected with C2 aperture = 50 um, convergence angle = 1.00 mrad with microprobe mode and with Electron Microscope Pixel Array Detector (EMPAD) GII (28) with dwell time 100 ps (Ref SS 1.), and with total dose 6 e-l2. All electron microscopy (EM) experiments are conducted at room temperature.

[0090] Tilt-Corrected Bright Field (tcBF). The tcBF experiment was collected using ThermoFisher Titan Themis Cryo S / TEM with a Field Emission Gun (X-FEG), a monochromator and probe spherical aberration correction with C2 aperture = 50 um, convergence angle = 10.0 mrad with with Electron Microscope Pixel Array Detector (EMPAD) GII with dwell time 100 ps and total dose 120 e- / A2. All EM experiments are conducted at room temperature.

[0091] He Pycnometry. A Micromeritics AccuPyc II 1340 gas pycnometer with He was employed to determine the bulk density of the novel MIM filler.

[0092] Electrospinning. Microfiber composite mats were fabricated using a Matregenix LS-300 electrospinner equipped with a rotating drum collector (d = 14 cm) set to 1000 RPM (7.3 m / s). Poly etherimide solutions (20 wt.% solids) were spun with the following parameters: 15 kV, 20 G blunt tip needle, 10 cm collector distance, and an extrusion rate of 1 mL / h.

[0093] SEM of Composite Fibers. A Hitachi TM3030Plus tabletop scanning electron microscope with a W filament electron source provided images of microfiber composite mats. SEM samples were prepared by cutting a 1 mm x 1 mm sample, drying in vacuo overnight, and seating on an SEM stub using carbon tape. Samples were then coated with 7 nm Au using a Denton Desk V Sputter Coater.

[0094] Synthetic Procedures TPE-PhOH Catalyst Selection

[0095] Scheme 1. Synthesis of TPE-PhOH.

[0096] Catalyst selection to produce TPE-PhOH: Various catalyst and ligand combinations were assessed to determine the most suitable conditions for formation of TPE-PhOH through Suzuki- Miayura cross-coupling reactions. All reactions occurred using a general procedure in which: A 20 ml scintillation vial was charged with potassium carbonate (1.31 mmol, 181 mg, 4.25 equiv.) l,l,2,2-tetrakis-(4-bromophenyl)ethylene (TPE-Br; 200 mg, 0.309 mmol, 1.00 equiv.), 4- hydroxyboronic acid (1.31 mmol, 181 mg, 4.25 equiv.), and catalyst combination (catalyst with inherent ligand or catalyst and exogenous ligand). The vessels were charged with 2.5 mL of THF (120 mM TPE-Br) and purged with nitrogen for 5 minutes. After which, the reactions were heated to 70 °C under stirring for 18 hours. Subsequently, 1,3,5-trimethoxybenzene (0.309 mmol, 52 mg, 1 eq) was added and the solutions were diluted to fully dissolve product. Yield and biproduct formation were determined byrH NMR spectroscopy where a small amount of reaction solution was transferred to an NMR tube and diluted with DMSO-de. Results of various trials are detailed in NMR spectra (Figure 5) and tabulated in Table 1.

[0097] Table 1. Catalyst identity, catalyst concentration, ligand identity, and yield of initial TPE- PhOH Suzuki-Miayura cross-coupling reactions.

[0098] TPE-PhOH Scale Up Conditions

[0099] Small scale screening of reaction conditions of TPE-PhOH: A 20 ml scintillation vial was charged with potassium carbonate (4.25 equiv.) and tetrabutylammonium bromide (TBAB; 0.5 equiv.), l,l,2,2-tetrakis-(4-bromophenyl)ethylene (TPE-Br; 20 - 320 mg, 0.031 - 0.247 mmol, 1.00 equiv.), 4-hydroxyboronic acid (4.25 - 6.00 equiv.), palladium acetate (Pd(OAc)z, 8.00 - 1.00 mol%), 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (Sphos, 12.0 - 1.50 mol%) and 1,3,5- trimethoxybenzene as an internal standard. The vial was purged with nitrogen to remove oxygen from the reaction vessel. Thereafter, 3 mb degassed 1,4-di oxane and 1 mL of degassed, deionized water was added under nitrogen and the reaction mixture was dispersed in a sonication bath for approximately 1 minute. Under vigorous stirring the resulting mixture was heated to 90 °C for 20 - 60 minutes. The reaction progress was monitored byrH NMR, where a small amount of the reaction mixture was transferred to NMR tubes and diluted with DMSO-rL.

[0100] 1 g scale synthesis of TPE-Ph-OH: A 20 ml scintillation vial was charged with potassium carbonate (870 mg, 6.30 mmol, 4.25 equiv.) and tetrabutylammonium bromide (TBAB; 239 mg, 0.741 mmol, 0.5 equiv.), l,l,2,2-tetrakis-(4-bromophenyl)ethylene (TPE-Br; 960 mg, 1.48 mmol, 1.00 equiv.), 4-hydroxyboronic acid (1.226 g, 8.88 mmol, 6.00 equiv.), palladium acetate [Pd(OAc)2, 3.3 mg, 0.015 mmol, 1.00 mol%], 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (SPhos, 9.1 mg, 0.022 mmol, 1.50 mol%) and 1,3, 5 -trimethoxybenzene (as internal standard, 82.3 mg, 0.49 mmol, 0.33 equiv.). The vial was purged with nitrogen to remove oxygen from the reaction vessel. Thereafter, 9 mL degassed 1,4-dioxane and 3 mL of degassed, deionized water was added under nitrogen and the reaction mixture was dispersed in a sonication bath for approximately 1 minute. Under vigorous stirring the resulting light orange suspension was heated to 100 °C for 60 minutes. During this time the reaction turned to a pale-yellow suspension. The reaction progress was monitored byJH NMR spectroscopy and confirmed the full conversion of the limiting reagent, TPE-Br. The reaction was cooled to room temperature using an ice bath and diluted with 10 mb of 1 M hydrochloric acid solution and extracted by 160 mL EtOAc (lx 80 m , 2x 40 mL). The combined organic layers were filtered through a bed of Celite and the filter bed was washed with copious amounts acetone. The yellow solution was dried over MgSCL and after filtration the solvents were evaporated. The resulting off white solid was dispersed in 7 mL acetone under sonication and precipitated by adding 100 mL MeCN to afford the product as off-white powder, that was collected by filtration and dried under vacuum at 100°C for 8 h (943 mg, 90 %). TPE-PhOH: ’H NMR (500 MHz, DMSO-# 5 9.52 (s, 4H), 7.44 (d, J = 8.5 Hz, 8H), 7.39 (d, J = 8.2 Hz, 8H), 7.06 (d, J = 8.2 Hz, 8H), 6.79 (d, J = 8.5 Hz, 8H) ppm.13C NMR (125 MHz, DMSO- d6) 8 157.10, 141.58, 139.67, 137.98, 131.40, 130.07, 127.47, 125.16, 115.68 ppm.

[0101] 10 g scale synthesis of TPE-Ph-OH: Under nitrogen inert gas atmosphere were 85 mL of degassed 1,4-dioxane and 30 mL degassed, deionized H2O added to a 250 mL two-neck flask equipped with a reflux condenser and stirrer. Potassium carbonate (8.70 g, 63.0 mmol, 4.25 equiv.) and tetrabutylammonium bromide (TBAB; 2.39 g, 7.41 mmol, 0.5 equiv.) were added and dissolved under stirring. Upon full dissolution of the salts, l,l,2,2-tetrakis-(4- bromophenyl)ethylene (TPE-Br; 9.60 g, 14.8 mmol, 1.00 equiv.) and 4-hydroxyboronic acid (12.26 g, 88.8 mmol, 6.00 equiv.) were added followed by palladium acetate [Pd(OAc)2, 33 mg, 0.148 mmol, 1.00 mol%] and 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (SPhos, 91 mg, 0.222 mmol, 1.50 mol%), and washed down with additional 5 mL degassed 1,4-dioxane. Under vigorous stirring, the resulting light orange suspension was heated to reflux within 20 min and then kept on reflux for another 60 minutes. During this time the reaction turned to a pale-yellow suspension. The reaction progress was monitored by1H NMR spectroscopy and confirmed the full conversion of the limiting TPE-Br starting material. The reaction was cooled to room temperature using an ice bath and diluted with 100 mL of 1 M hydrochloric acid solution and extracted by 400 mL EtOAc (lx 250 mL, 2x 75 mL). The combined organic layers were filtered through a bed of Celite and the filter bed washed with copious amounts acetone. The yellow solution was dried over MgSO4 and after filtration the solvents were evaporated. The resulting off white solid was under sonication dispersed in 40 mL acetone and precipitated by adding 250 mL MeCN to afford the product as off-white powder, that was collected by filtration and dried under vacuum at 100°C for 8 hours (9.95 g, 95%). The1H NMR spectrum fully agrees with the smaller batch size. 50 a scale synthesis of TPE-Ph-OH: Under nitrogen inert gas atmosphere, 1,4-di oxane (440 mL, degassed) and water (140 mL, degassed) were added to a 1 L three-neck flask equipped with a reflux condenser and stirrer. Potassium carbonate (43.5 g, 315 mmol, 4.25 equiv.) and tetrabutylammonium bromide (TBAB; 11.9 g, 37.0 mmol, 0.5 equiv.) were added and dissolved under mechanical stirring. Upon full dissolution of the salts, l,l,2,2-tetrakis-(4- bromophenyl)ethylene (TPE-Br; 48.0 g, 74 mmol, 1.00 equiv.) and 4-hydroxyboronic acid (61.3 g, 444 mmol, 6.00 equiv.) were added followed by palladium acetate [Pd(OAc)2, 166 mg, 0.741 mmol, 1.00 mol%] and 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (SPhos, 456 mg, 1.11 mmol, 1.50 mol%), and washed down with additional each 10 mL of degassed 1,4-dioxane and water. Under vigorous stirring the resulting light orange suspension was heated to reflux within 40 min and then kept on reflux for another 150 minutes. During this time the reaction turned to a paleyellow suspension. The reaction progress was monitored by 'H NMR spectroscopy and confirmed the full conversion of the limiting TPE-Br starting material. The reaction was cooled to room temperature using an ice bath. The reaction mixture was separated into 3 batches for better handling in the work-up. Each batch was diluted with 200 mL of 1 M hydrochloric acid solution and extracted by 400 mL EtOAc (lx 250 mL, 2x 75 mL). The combined organic layers were washed filtered through a bed of Celite and the filter bed was washed with copious amounts acetone. The yellow organic layers were dried over MgSCL and after filtration the reaction mixtures were combined, and the solvent was evaporated under vacuum. The resulting off white solid was under sonication dispersed in 100 mL acetone and precipitated by adding 500 mL MeCN to afford the product as off-white powder, that was collected by filtration and dried under vacuum at 100°C for 8 h (44.3 g, 85%). The 'H NMR spectrum fully agrees with the smaller batch size.

[0102] Crystallization of TPE-PhOH into Hydrogen-bonded Single Crystals

[0103] SCI : A solution of TPE-PhOH (20 mg / mL) in ethyl acetate was stirred at 40 °C until complete dissolution was achieved (10 minutes). The solution was then evaporated under reduced pressure until 1 / 3 solution remained and small crystals began to form. The solution was allowed to come to room temperature over the course of an hour followed by cooling in a refrigerator for 18 hours. Crystals were analyzed by SCXRD to determine the hydrogen-bonded crystal structure model. More details on crystallization and crystal structure model are available in section E.

[0104] SC2: Crystals were prepared identically to SCI with a TPE-PhOH sample synthesized with Pd(PPli3)4 catalyst. A solution of TPE-PhOH (20 mg / mL) in ethyl acetate was stirred at 40 °C until complete dissolution was achieved (10 minutes). The solution was then evaporated under reduced pressure until 1 / 3 solution remained and small crystals began to form. The solution was allowed to come to room temperature over the course of an hour followed by cooling in a refrigerator for 18 hours. Crystals were analyzed by SCXRD to determine the hydrogen-bonded crystal structure model. More details on crystallization and crystal structure model are available in section E.

[0105] Reactions of TPE-PhOH Crystals with SiMeiCh

[0106] Vapor Introduction:

[0107] TPE-PhOH single crystals were prepared as detailed above. The mother liquor was discarded leaving behind monomer crystals. These crystals were subjected to SiMe2Ch (0.5 mL / g monomer) vapor for 7 days to produce 2D MIMs.

[0108] Solution Introduction:

[0109] TPE-PhOH single crystals were prepared as detailed above. The crystals were filtered out and washed with hexanes. The crystals were then submerged in hexanes and SiMe2Ch (0.5 mL / g monomer) was added. Crystals were allowed to react over 24 hours. After reaction, the HC1 produced was quenched using triethyl amine.

[0110] Work Up:

[0111] 2D MIMs were dissolved in acetone and precipitated into a 1 : 1 v / v mixture of isopropanol and water. The precipitated material were square sheets attributed to 2D MIMs. These solids were collected via centrifugation or filtration and dried under vacuum at 75 °C overnight to produce a pale-yellow powder (largest batch yielded: 12.5 g, 75% isolated yield 2D MIMs).

[0112] Electrospinning of 2D MIM / Ultem Composites to Form Fibers

[0113] Microfiber composite mats were fabricating using a Matregenix LS-300 electrospinner equipped with a rotating drum collector (d = 14 cm) set to 1000 RPM (7.3 m / s). Polyetherimide solutions (20 wt. % solids) were spun with the following parameters: 15 kV, 20 gauge blunt tip needle, 10 cm collector distance, and an extrusion rate of 1 mL / hour. The mats were removed from the drum and fixed vertically to dry in ambient conditions for 18 h before being transferred to a Lindberg Blue M vacuum oven. The samples were dried in vacou for 18 hours at 25 °C following by 1 hour each at 60, 80, 100, 120, 140, and 160 °C. Tensile samples were prepared by cutting the microfiber composite mats into 5 x 30 mm rectangles. Tensile experiments were performed on a TA Instruments DHR-3 at 25 °C. These measurements were made on a Smart Swap™ tensile geometry with a 20 mm gap operating at 200 |im / second. The data was analyzed using the TA Instruments TRIOS software to identify the ultimate tensile stress (UTS), strain at break, and Young’s modulus (E’). To accurately calculate tensile properties, a density-based correction was employed to account for void space throughout the fibrous sample. This was accomplished using Eqn 1.

[0114] Determining Bulk Density Through He Pycnometry

[0115] He pycnometry was employed to determine the bulk density of the novel MIM filler, which was measured at 1.195 g / cm3. The density of the composite fibers follows the rule of mixtures, and thus, is readily calculated using the known composition of the fibers. Therefore, the tensile data was corrected by solving for the thickness (Eqn. 1). This value is the true thickness of the cross-section of a semiporous sample. A Hitachi TM3030Plus tabletop scanning electron microscope provided images of the microfiber composite mats.

[0116] Hydrolytic Stability of 2D MIMs

[0117] The stability of 2D MIMs, when exfoliated in acetone, was tested through 'H NMR degradation experiments. First, a solution of 2D MIM in acetone-d6 was made (with internal standard 1,3,5-dimethoxybenzene) was made. Then, the solution was diluted with water until the solution was 20% v / v water. The solution was separated into two NMR tubes one of which was analyzed at time 1 hour and again at time 24 hours (after resting at room temperature). The other NMR tube was heated to 55 °C for 22 hours then analyzed via 1H NMR. The results of this study can be found in below.

[0118] Hydrolytic Stability of 2D MIM / Ultem™ Composites

[0119] The hydrolytic stability of 2D MIM / Ultem™ composites was determined through the following methods. The composite fibers were exposed to boiling water for 1 h and then tensile testing experiments were repeated. We note that all substrates were cut from the same electrospun composite films as the original tensile testing samples allowing for direct comparison between the boiled and not boiled samples.

[0120] Characterization of 2D MIMs

[0121] UV / Vis Spectroscopy and Fluorescence Spectroscopy were done (See Figures 6 and 7).

[0122] Single Crystal X-Ray Diffraction Structure Models SCI: TPE-PhOH Hydrogen-bonded Network with Ethyl Acetate Channels (SCI, CX3056)

[0123] Hydrogen-bonded networks were formed through controlled slow evaporation methods. A solution of TPE-PhOH in ethyl acetate was formed (20 mg / mL, 28.6 mM). The solution was sonicated to ensure complete dissolution. The solution was loaded into a 500 mL round bottom flask and subjected to rotary evaporation. The solutions was first rotated under ambient pressure at 100 rpm and 40 °C for 10 minutes to ensure complete dissolution. After which the solution was brought to 200 mbar and 40 °C while rotating at 100 rpm until crystallites formed (volume reduced by 2 / 3). After which, the solution was cooled to 3 °C overnight. The crystals were analyzed using SCXRD and the crystal structure was determined.

[0124] TPE-PhOH Co-Crvstals with TPPO (SC2, CX3194)

[0125] A solution of TPE-PhOH in ethyl acetate was formed (20 mg / mL, 28.6 mM). The solution was sonicated to ensure complete dissolution. The solution was loaded into a 500 mL round bottom flask and subjected to rotary evaporation. The solutions was first rotated under ambient pressure at 100 rpm and 40 °C for 10 minutes to ensure complete dissolution. After which the solution was brought to 200 mbar and 40 °C while rotating at 100 rpm until crystallites formed (volume reduced by about half). After which, the solution was cooled to 3 °C overnight. The crystals were analyzed using SCXRD and the crystal structure was determined.

[0126] Hydrolytic Stability of 2D MIMs and Composites

[0127] 1H NMR spectra of 2D MIMs in wet acetone (20% H2O in acetone-d6) indicate that the dispersed material is hydrolytically stable in the exfoliated state. The top spectrum was obtained from a solution that was heated for 22 hours at 55 °C. This study tested the hydrolytic stability of the 2D MIM as a dispersion in wet acetone. The solution was then analyzed using 1H NMR spectroscopy after Ih and 24h and then heated to 55 °C for 22h. Under all conditions, the 1H NMR spectra remain similar with the aromatic peaks (region from 6.5 to 7.5 ppm) and the methyl proton (at -0.08 ppm) remaining unchanged. These experiments indicate that, in the presence of water, the 2D MIM maintains chemical stability at room temperature and when heated.

[0128] Tensile Testing

[0129] As shown in Figure 17, show that the average fiber diameters of <5 pm that do not change when subjected to these conditions. However, the post treatment, the fiber mat tensile bars do fray and the alignment is slightly reduced which leads to some low strain yielding which does affect the magnitude of some of the measurements post treatment. Incorporation of highly exfoliated 2D MIM filler exhibited higher ultimate stress and tensile modulus (E’) up to 2.5 wt% MIMs. The trends remained after the extreme thermal treatment in boiling water for 1 hour (data not shown). Samples comprised of 2.5 wt% MIM exhibited the highest tensile modulus and UTS before and after treatment, but all compositions displayed reduced strain at break compared to nascent UltemTM.

[0130] Table 2. Crystal collection and structure refinement data for SCI.

[0131] Table 3. Crystal collection and structure refinement data for SC3.

[0132] Table 4. Compiled single crystal collection and structure refinement data.

[0133] Abbreviations used herein

[0134] 2D. two dimensional

[0135] 4D-STEM. Four dimensional scanning transmission electron microscopy AFM. Atomic force microscopy

[0136] CP-MAS. Cross-polarization magic-angle spin

[0137] CP-MG. Carr-Purcell-Meiboom-Gill

[0138] EDX. Electron-dispersive x-ray spectroscopy

[0139] EELS. Electron energy loss spectroscopy EM. Electron microscopy

[0140] EtOAc. Ethyl acetate

[0141] FFT. Fast Fourier transform

[0142] FT-IR. Fourier-transform infrared

[0143] HAADF. High-angle annular dark-field

[0144] HOAc. Acetic acid iDPC. Integrated differential phase contrast

[0145] MeCN. Acetonitrile

[0146] MIM. Mechanically interlocked material

[0147] NMP. N-methylpyrrolidone

[0148] NMR. Nuclear magnetic resonance

[0149] Pd(OAc)2. Palladium di acetate

[0150] Pd(PPh3)4. Palladium tetrakis(triphenylphosphine) PXRD. Powder x-ray diffraction

[0151] QNM. Quantitative NanoMechanical

[0152] SAED. Selective area electron diffraction

[0153] SCXRD. Single crystal x-ray diffraction

[0154] SEM. Scanning electron microscopy

[0155] SEND. Scanning electron nanobeam diffraction

[0156] SPhos. 2-dicyclohexylphsphino-2’, 6’ -dimethoxybiphenyl STEM. Scanning transmission electron microscopy TBAB. Tetrabutylammonium bromide tcBF. Tilt-corrected bright field

[0157] TEM. Transmission electron microscopy

[0158] TGA. Thermogravimetric analysis

[0159] THF. Tetrahydrofuran

[0160] TPE. Tetraphenyl ethylene

[0161] TPE-Br. 1 , 1 ,2,2-tetrakis(4-bromophenyl)ethene

[0162] TPE-PhOH. 1, l,2,2-tetrakis(4-hydroxybiphenyl)ethylene TPPO. Triphenylphosphine oxide

[0163] UV / Vis. Ultraviolet / visible XPhos. 2-dicyclohexylphosphino-2’, 4’, 6’ -triisopropylbiphenyl

[0164] XPS. X-ray photoelectron spectroscopy

[0165] References

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[0176] 12. L. Chen et al., Enhancing the Toughness and Strength of Polymers Using Mechanically Interlocked Hydrogen Bonds. J. Am. Chem. Soc. 146, 1109-1121 (2024).

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[0181] 17. M. Hasegawa, Y. Suzuki, Four-center type photopolymerization in the solid state: Poly- 2,5-distrylpyrazine. J. Polym. Sci. PartB 5, 813-815 (1967).

[0182] 18. K. Hema et al., Topochemical polymerizations for the solid-state synthesis of organic polymers. Chem. Soc. Rev. 50, 4062-4099 (2021).

[0183] 19. P. Kissel et al., A two-dimensional polymer prepared by organic synthesis. Nature Chem. 4, 287-291 (2012). 0. P. Kissel, D. J. Murray, W. J. Wulftange, V. J. Catalano, B. T. King, A nanoporous two- dimensional polymer by single-crystal-to-single-crystal photopolymerization. Nature Chem. 6, 774-778 (2014). 1. M. J. Kory et al., Gram-scale synthesis of two-dimensional polymer crystals and their structure analysis by X-ray diffraction. Nature Chem. 6, 779-784 (2014). Q. Huang et al., Dynamic molecular weaving in a two-dimensional hydrogen-bonded organic framework. Chem 7, 1321-1332 (2021). B. Lesiak et al., C sp2 / sp3hybridisations in carbon nanomaterials - XPS and (X)AES study. Appl. Surf. Set. 452, 223-231 (2018). S. Armyanov et al., XPS and p-Raman study of nanosecond-laser processing of poly(dimethylsiloxane) (PDMS). Nucl. Instrum. Methods Phys. Res. Sect. B 360, 30-35 (2015). A. M. Evans et al., Two-Dimensional Polymers and Polymerizations. Chem. Rev. 122, 442-564 (2022). A. A. Saddik, A. A. K. Mohammed, S. K. Talloj, A. M. Kamal El-Dean, O. Younis, Solvatochromism of new tetraphenylethene luminogens: integration of aggregation- induced emission and conjugation-induced rigidity for emitting strongly in both solid and solution state. RSC Adv. 14, 6072-6084 (2024). Y. Yu et al., Dose-Efficient Cryo-Electron Microscopy for Thick Samples using Tilt- Corrected Scanning Transmission Electron Microscopy, Demonstrated on Cells and Single Particles. bioRxiv, 2024.2004.2022.590491 (2024). H. T. Philipp et al., Very-High Dynamic Range, 10,000 Frames / Second Pixel Array Detector for Electron Microscopy. Microsc. Microanal. 28, 425-440 (2022).

Claims

CLAIMSWe claim:

1. A mechanically interlocked two-dimensional polymer.

2. The mechanically interlocked two-dimensional polymer of claim 1, wherein the mechanically interlocked two-dimensional polymer comprises siloxane linkages.

3. The mechanically interlocked two-dimensional polymer of any one of claims 1-2, wherein the mechanically interlocked two-dimensional polymer is prepared from a crystalline monomer.

4. The mechanically interlocked two-dimensional polymer of any one of claims 1-3, wherein the mechanically interlocked two-dimensional polymer is prepared from TPE-PhOH.

5. The mechanically interlocked two-dimensional polymer of any one of claims 1-4, wherein the mechanically interlocked two-dimensional polymer is prepared from a silane.

6. The mechanically interlocked two-dimensional polymer of claim 5, wherein the silane is a dialkyldichloro silane.

7. The mechanically interlocked two-dimensional polymer of claim 6, wherein the dialkyldichloro silane is SiNfeCh.

8. The mechanically interlocked two-dimensional polymer of any one of claims 1-7, wherein the mechanically interlocked two-dimensional polymer is exfoliated.

9. A dispersion comprising the mechanically interlocked two-dimensional polymer of any one of claims 1-8 and a solvent.

10. The dispersion of claim 9, wherein the solvent comprises an organic solvent, optionally wherein the organic solvent comprises acetone, isopropyl alcohol, tetrahydrofuran, ethyl acetate, or any combination thereof.

11. A polymer composite comprising the mechanically interlocked two-dimensional polymer of any one of claims 1-8 and a second polymer.

12. The polymer composite of claim 11, wherein the second polymer is poly(ether imide).

13. The polymer composite of any one of claims 11-12, wherein the polymer composite comprises between 0.1 and 10.0 wt% of the mechanically interlocked two-dimensional polymer.

14. A fiber comprising the polymer composite according to any one of claims 11-13, wherein the fiber has average fiber diameter less than 5 pm.

15. A method for preparing a mechanically interlocked two-dimensional polymer, the method comprising contacting a crystalline monomer with a crosslinking reagent, wherein the crystalline monomer comprises two sets of parallel linear structures and the two sets of parallel linear structures tread through each other.

16. The method of claim 1 , wherein the crosslinking reagent is a silane, a phosphene, or a chloroformate.

17. The method of claim 16, wherein the crosslinking reagent is a di alkyl di chloro silane.

18. The method of claim 17, wherein the dialkyldicholoro silane is SiNfeCb.

19. The method of any one of claims 15-18, wherein the crystalline monomer comprises TPE-PhOH.

20. The method of any one of claims 15-19, wherein the crystalline monomer is contacted with reagent vapor.

21. The method of any one of claims 15-19, wherein the crystalline monomer is contacted with the reagent in a non-solvent of the crystalline monomer.

22. The method of claim 21, wherein the non-solvent of the crystalline monomer comprises alkanes, optionally wherein the alkanes comprise one or more hexane isomers.

23. The method of any one of claims 15-22 further comprising exfoliating the mechanically interlocked two-dimensional polymer.

24. The method of any one of claims 15-23, wherein the method prepares the mechanically interlocked two-dimensional polymer according to any one of claims 1-8.

25. A method of preparing a dispersion, the method comprising dispersing the mechanically interlocked two-dimensional polymer according to any one of claims 1-8 or prepared by the method according to any one of claims 15-23 in a solvent, optionally wherein the solvent is an organic solvent.

26. A method of preparing a polymer composite, the method comprising mixing the mechanically interlocked two-dimensional polymer according to any one of claims 1-8 or prepared according the method of any one of claims 15-23 and a second polymer, optionally wherein the second polymer is a poly(ether imide).

27. A method of preparing a fiber, the method comprising electrospinning the polymer composite according to any one of claims 11-13 or prepared according to the method of claim 26.

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